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Took the p177x out after work to ride around. WOT for about 1/2 a mile. Afterward, the idle wouldnt come down from 1700+. I have the idle set around 1200. Air leak maybe? I pulled the jets, cleaned em up, adjusted the mixture again, but its still not quite where it was before. Also, Now theres a little hesitation off the line. Guess i need to baby it more…
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Molto Verboso
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Check for a head leak
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hibbert wrote:
Check for a head leak
Thanks. Will do.

When i let it sit for a bit, then start it, it seems to idle ok. After a mile or so, the idle sits high again. That still sound like a head leak?
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coastalviews wrote:
Thanks. Will do.

When i let it sit for a bit, then start it, it seems to idle ok. After a mile or so, the idle sits high again. That still sound like a head leak?
That sounds even more like a head leak. Or some other air leak, but definitely an air leak.

It'll only get worse until you either find and fix it or seize it. Those are the only two outcomes.
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chandlerman wrote:
That sounds even more like a head leak. Or some other air leak, but definitely an air leak.

It'll only get worse until you either find and fix it or seize it. Those are the only two outcomes.
Got it up to running temp and sprayed the hell out of it with carb cleaner. All around the head, and under the carb. Nothing happened. Going to take it for a little spin now, and see what happens.
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Same thing. Runs and idles, but when i get on the throttle, the idle climbs way up, and sits there.
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you definitely have a leak, you just haven't found it yet.

check for oil dripping from under the flywheel and drain a little oil and see if it smells like gasoline.

That'll check your seals. If the oil smells like gas, you're going to have to go deep into the cases to fix it.
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chandlerman wrote:
you definitely have a leak, you just haven't found it yet.

check for oil dripping from under the flywheel and drain a little oil and see if it smells like gasoline.

That'll check your seals. If the oil smells like gas, you're going to have to go deep into the cases to fix it.
So theres always been a coating of exhaust/oil on the back of the engine. But nothing ever wet/dripping. I drained a little oil, it was pretty dark, and had *maybe* the slightest hint of gasoline. Would it be obvious?
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coastalviews wrote:
So theres always been a coating of exhaust/oil on the back of the engine. But nothing ever wet/dripping. I drained a little oil, it was pretty dark, and had *maybe* the slightest hint of gasoline. Would it be obvious?
It'll be pretty obvious when it's seal replacement time.

I don't recall... Have you cleaned your idle jet? A blocked idle jet can also cause a lean idle, but it's usually more consistent.

Next time it's racing, pull your choke and see if that helps.
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chandlerman wrote:
It'll be pretty obvious when it's seal replacement time.

I don't recall... Have you cleaned your idle jet? A blocked idle jet can also cause a lean idle, but it's usually more consistent.

Next time it's racing, pull your choke and see if that helps.
I pulled the idle, and jet stack, blew through em and wiped em on my shirt. Ill pull em again, and give a good scrub.


*Sprayed em down, and hit the carb with some cleaner. Fired right up, and ran fine. Time will tell i suppose.
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The air mixture on the back of the carburator can make your engine run like hell. I found it to be very sensitive to idle and to restart. Too lean and it will make your idle very high and you can smell the engine heat, too rich and you will foul the plug and it wouldn't restart after being hot. You can also tell by how the engine response is. Have you messed with the air mixture? if after a hot run it happens again try going counterclockwise(richen it) in 1/4 turns increments. You should be able to tell right of way. Assuming your engine idles good.

Also as other have said, check your head torque and take a look at your sparkplug as well. Most of my high revving issues in the past were air mixture related and I will tell you that the screw is very sensitive too.
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Oh that ended up just being a dirty idle jet or something. Im on to new problems now. Got a new coil, points, capacitor, and its back to 20 kicks to start, and dying at stoplights.
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coastalviews wrote:
Oh that ended up just being a dirty idle jet or something. Im on to new problems now. Got a new coil, points, capacitor, and its back to 20 kicks to start, and dying at stoplights.
Sounds like your dirty idle jet is back.

What's the state of the gas tank? You might want to clean the tank and also add a fuel filter into the line if the tank is a mess.
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When i picked up the scoot, i washed out the tank with dish soap/water. It actually looked good inside. I have noticed some very fine back powder(?) swirling around. Is it possible the in-tank filter isnt up to snuff? Its a fast flow tap.
⚠️ Last edited by coastalviews on UTC; edited 1 time
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coastalviews wrote:
Oh that ended up just being a dirty idle jet or something. Im on to new problems now. Got a new coil, points, capacitor, and its back to 20 kicks to start, and dying at stoplights.
Check compression ?
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Well, got a new regulator, ht coil, condenser, and points on the p. No spark. Facepalm emoticon . Battery's @ 11.98 with ign off, 11.65 with ign on. Going to put it on the charge. I know there's a fuse behind the battery(its intact). There's not another one hidden somewhere is there?

It got me home friday, though it stalled at light's a few times, then saturday it stalled much more at lights.
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The battery has nothing to do with the spark, but it's either not charging (probably) or you either have some sort of parasitic drain in the system.

Moto64 had a good idea checking compression. You can test the spark while the plug is out and make sure you have a healthy looking spark.
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True. Ill do it right now.

*Just under 125psi with fuel tap open, and WOT.
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Definitely not compression. (under 90 lbs or so would be worrisome)

So back to spark and/or carb. I'm kind've feeling like it's a spark or timing issue at the moment.
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👍🏻 Just rechecked my new regulator, wiring looks good. I feel like its the new ht coil, or the points/condenser. The new coil is the blue one(ducati?) and went on easy. The points/condenser got installed and re-soldered. Points are .035 @ TDC, and stator is turned all the way counter-clockwise to put me @19*BTDC. This is the way i believe i had it before.

Progress i think. I tested my old condenser(off the bike) with a multimeter and i can watch it build a charge on ohms, then drop to 0 on vdc.

The new one in the bike(points open) stays on 0 then and fluctuates a little back and forth. Nothing like the old one.
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No luck. Still no spark. Im going through the wiring diagram trying to figure what all is involved with the ignition circuit that could be faulty.

Do the points have anything between them and the stator plate?
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coastalviews wrote:
No luck. Still no spark. Im going through the wiring diagram trying to figure what all is involved with the ignition circuit that could be faulty.

Do the points have anything between them and the stator plate?
Can you post a photo of your ignition? That'll help a lot.
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chandlerman wrote:
Can you post a photo of your ignition? That'll help a lot.
The stator?
Forum member supplied image with no explanatory text
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Jet Eye Master
PX221 MHR, O tuned PX200, PX181, PX125 and some motorbikes
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coastalviews wrote:
The stator?
Long time ago since I did anything with points. Pretty sure that grey power wire should connect to the condenser. Looks like it's broken off; might just be the camera angle.

Timing looks a long way advanced. 21 degrees is a good number for points.
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Jack221 wrote:
Pretty sure that grey power wire should connect to the condenser. Looks like it's broken off; might just be the camera angle.
I'm thinking the exact same thing. I've never seen a condenser with a grey wire. All mine are yellow, not that it means anything.

I think OP said he strobed it to 21 BTDC, so timing should be okay once the condenser gets replaced.
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The grey wire is in fact connected. Sorry about the angle. The black, and grey wire are both connected to the condenser. Where i have the stator spun to, was ~19* when it was running.
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